2 research outputs found
Glycan Imaging in Intact Rat Hearts and Glycoproteomic Analysis Reveal the Upregulation of Sialylation during Cardiac Hypertrophy
In
the heart, glycosylation is involved in a variety of physiological
and pathological processes. Cardiac glycosylation is dynamically regulated,
which remains challenging to monitor <i>in vivo</i>. Here
we describe a chemical approach for analyzing the dynamic cardiac
glycome by metabolically labeling the cardiac glycans with azidosugars
in living rats. The azides, serving as a chemical reporter, are chemoselectively
conjugated with fluorophores using copper-free click chemistry for
glycan imaging; derivatizing azides with affinity tags allows enrichment
and proteomic identification of glycosylated cardiac proteins. We
demonstrated this methodology by visualization of the cardiac sialylated
glycans in intact hearts and identification of more than 200 cardiac
proteins modified with sialic acids. We further applied this methodology
to investigate the sialylation in hypertrophic hearts. The imaging
results revealed an increase of sialic acid biosynthesis upon the
induction of cardiac hypertrophy. Quantitative proteomic analysis
identified multiple sialylated proteins including neural cell adhesion
molecule 1, T-kininogens, and α<sub>2</sub>-macroglobulin that
were upregulated during hypertrophy. The methodology may be further
extended to other types of glycosylation, as exemplified by the mucin-type
O-linked glycosylation. Our results highlight the applications of
metabolic glycan labeling coupled with bioorthogonal chemistry in
probing the biosynthesis and function of cardiac glycome during pathophysiological
responses
Glycan Imaging in Intact Rat Hearts and Glycoproteomic Analysis Reveal the Upregulation of Sialylation during Cardiac Hypertrophy
In
the heart, glycosylation is involved in a variety of physiological
and pathological processes. Cardiac glycosylation is dynamically regulated,
which remains challenging to monitor <i>in vivo</i>. Here
we describe a chemical approach for analyzing the dynamic cardiac
glycome by metabolically labeling the cardiac glycans with azidosugars
in living rats. The azides, serving as a chemical reporter, are chemoselectively
conjugated with fluorophores using copper-free click chemistry for
glycan imaging; derivatizing azides with affinity tags allows enrichment
and proteomic identification of glycosylated cardiac proteins. We
demonstrated this methodology by visualization of the cardiac sialylated
glycans in intact hearts and identification of more than 200 cardiac
proteins modified with sialic acids. We further applied this methodology
to investigate the sialylation in hypertrophic hearts. The imaging
results revealed an increase of sialic acid biosynthesis upon the
induction of cardiac hypertrophy. Quantitative proteomic analysis
identified multiple sialylated proteins including neural cell adhesion
molecule 1, T-kininogens, and α<sub>2</sub>-macroglobulin that
were upregulated during hypertrophy. The methodology may be further
extended to other types of glycosylation, as exemplified by the mucin-type
O-linked glycosylation. Our results highlight the applications of
metabolic glycan labeling coupled with bioorthogonal chemistry in
probing the biosynthesis and function of cardiac glycome during pathophysiological
responses